This invention relates to a process for recovery of tantalum and, optionally, niobium values from an impure source containing tantalum, tungsten, iron, titanium and other impurities. More particularly it relates to a process for recovery of high purity mixed oxides of tantalum and niobium from an impure source containing tantalum and, optionally, niobium, and tungsten, iron, titanium, and other impurities.
Tungsten carbide scrap material can contain titanium carbide tantalum carbide and/or niobium carbide. The processing of such scrap material can involve either acid or caustic digestion of said scrap material to remove cobalt and/or tungsten. The sludges generated from said either acid of digestion of said scrap material can contain tantalum, niobium, tungsten, iron, titanium, and other impurities. These sludges are representative of the type of impure source of this disclosure.
High purity tantalum and/or niobium compounds can be produced by ion exchange or solvent extraction processes. Said ion exchange or solvent extraction proesses require large outlays of equipment and raw materials. Such methods are described in the following U.S. Pat. Nos.: 3,107,976, 2,895,793, 2,880,060, 2,819,945, 4,182,744, 4,069,268, 4,065,405, 3,972,710.
A process for producing high purity tantalum and/or niobium compounds from impure material without large outlays of equipment and raw materials is economically desirable.